9/11 attack: 20 haunting photos of World Trade Centre that sum up the tragedy

9/11 attack: 16 years on, the wound of the September 11 attack is still fresh in the minds and hearts of many. The Twin Towers of the World Trade Centre were a familiar sight to New Yorkers for decades and for many they were a reassuring sight - something on the lines of the Statue Of Liberty, they had become an icon of American spirit. But after September 11, 2001 things changed for the United States as well as for the people living there. The Twin Towers were destroyed when Al Qaeda terrorists hijacked two passenger jets and crashed them into the towers and brought them down in never-before-seen scenes of mass tragedy that caused thousands of deaths - nearly 3000 people. Another hijacked plane crashed into the Pentagon in Virginia and the fourth one crashed into an open field in Pennsylvania. Here are some of the haunting photos of the post tragedy photos from September 11 attack that sum up the tragedy. [United Airlines Flight 175 flied low towards the south Tower of the WTC, shortly before alamming into the structure. The north tower burns after an earlier attack by a hijacked airliner in New York City. (Photo: Reuters)]

On Sptember 11, American Airlines Flight 175 closes in on World Trade Center Tower 2 in New York, just before impact. (Photo: AP)

The second tower of the World Trade Center bursts into flames after being hit by a hijacked airplane in New York September 11, 2001. (Photo: Reuters)

Smoke pours from a gaping hole and the upper floors of the World Trade Centre's North Tower, shortly after hijackers crashed American Airlines Flight 11 into the buiding on September 11, 2001. (Photo: AP)

The remaining tower of New York's World Trade Center, Tower 2, dissolves in a cloud of dust and debris about a half hour after the first twin tower collapsed September 11, 2001. (Photo: Reuters)

At 9.59 AM, after burning for 56 minutes, the South Tower of New York's World Trade Centre began to collapse after a terrorist attack. (Photo: AP)

A rescue helicopter surveys damage to the Pentagon as firefighters battle flames after a hijacked airplane crashed into the U.S. military headquarters outside of Washington, September 11, 2001. (Photo: Reuters)

Dist, smoke and ash engulf buildings around the World Trade Centre in NYC, after the collapse of both towers on Sep 11. Photo has been taken by the New York City Police Department.

The Falling Man. A man whose identity remains upknown, falls headfirst after jumping from the north tower of New York's World Trade Center after it was attacked. This Now famous photograph has becoe iconic and ispired an article and documentary movie. (Photo: AP)

Flames and smoke pour from the Pentagon building adter a direct, devastating hit from an aircraft. (Photo: AP)

A group of firefighters walk amid rubble near the base of the destroyed south tower of the World Trade Center in New York September 11, 2001. (Photo: Reuters)

New York City firefighters and other emergency personnel survey the World Trade Center collapse area near Vessey and Greenwich Streets after the World Trade Center collapse. (Photo: Reuters)

The wreck of the World Trade Center smolders in the background as a man passes a subway stop near ther World Trade Center Towers after planes crashed into each of the buildings in New York. (Photo: Reuters)

The damaged area of the Pentagon building, where a commercial jetliner slammed into it September 11, is seen in the early morning at sunrise with the U.S. Capitol Building in the background. (Photo: Reuters)

Firemen work around the World Trade Center after both towers collapsed in New York. (Photo: Reuters)

A group of firefighters walk near the remains of the destroyed World Trade Center in New York on September 11, 2001. (Photo: Reuters)

A group of firefighters stand in the street near the destroyed World Trade Center in New York on September 11, 2001. (Photo: Reuters)

One side of the Pentagon buiding is exposed after a hijacked aircraft crashed into it on September 11, 2001. (Photo: AP)

People covered in dust walk over debries near the World Trade Centre in New York City On September 11, 2001. (Photo: AP)

An arial view shows only a small portion of the scene where the twin towers collapsed following the Sept 11 terrorist atack. (Photo: US Navy)